New sulfur-oxygen mixed-donor ligand N,N'-dimethyl-piperazine-3-oxo-2-thione (Me2pipto) and its Ni(II) and Fe(II) complexes.

Structural and electronic features of the novel title sulfur-oxygen donor ligand Me(2)pipto (1), are discussed in comparison with those of the corresponding dithione ligand Me(2)pipdt. A tuning of the electronic and coordination properties of the ligand, relatable to the soft/hard power of the donor atoms, is achieved. Coordination properties have been checked towards Ni(II) and Fe(III) cations obtaining [Ni(Me(2)pipto)(3)](BF(4))(2) (2) and [Fe(Me(2)pipto)(3)](BF(4))(2) (4) complexes, which show significant differences when compared with the corresponding reaction products when using Me(2)pipdt.